The Milwaukee Journal Sentinel said the Illinois Environmental Protection Agency is seeking enforcement action over Macoupin Energy. The pollution-control agency said the company isn't adequately addressing groundwater problems at its Shay 1 mine in Carlinville, Ill.

The company said it won't comment and will defend itself vigorously.

Macoupin is one of four Illinois mines owned by billionaire Christopher Cline. He plans to build a $1.5 billion iron-ore mine in Wisconsin if the Legislature rewrites mining laws to the company's satisfaction.

Groundwater at the Illinois mine was polluted by a previous company, but Cline's company agreed to clean it up when it purchased the mine.

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